Tesla Motors [NSDQ:TSLA] is extending the drivetrain warranty of its Model S electric car to match the already-expansive coverage offered for the battery pack. With the newly-extended warranty, an 85-kilowatt-hour Model S will be covered for eight years with unlimited mileage, the company announced in a recent blog post. The 60-kWh Model S will have eight years or 125,000 miles of coverage.

That would seem like a fairly generous policy at any time, but Tesla CEO Elon Musk believes the company should have done things this way from the beginning. He said Tesla stands by the belief that electric cars are inherently more reliable than anything with an internal-combustion engine—noting that they have fewer moving parts to break, among other things—and that the warranty policy should reflect that.

However, it may also be at least partially a response to recent media coverage of Model S reliability issues. Both Motor Trend and Edmunds have had drive units in their long-term test cars replaced—four times in the latter's case—and an expanded warranty could help reassure customers spooked by these reports.

The Tesla Model S drivetrain was previously covered under the four-year/50,000-mile vehicle warranty, which fell somewhat short of the coverage offered by many of Tesla's competitors. So the new warranty will fill a gap in the current coverage.

It will also cost Tesla money in the short term, Musk acknowledged, but will likely be well worth it compared to the long-term public-relations benefits of being seen as a company that takes care of its customers.